Undulated shed looms with electromagnetic shuttle drive are already known. In previously known shuttle drives of this type there is the danger that the synchronism between the beating up of the filling threads and the transporting of the shuttles is lost. As a result, there can be relative displacements of the shuttles with respect to each other or shuttles may even drop out of the field of force. Disturbances of this kind, for instance, can occur in case of increased rubbing of the warp yarns against the shuttles, upon the catching of a filling yarn in the warp yarns, or in case of a sudden stopping of the loom.
Also in one known magnetic drive device for the shuttles of an undulated shed loom, the shuttles are made in disk shape and are transported through the sheds by means of a conveyor belt which is provided with electromagnets. Due to the use of electromagnets, the magnets and the shuttles become very warm, and special cooling elements may have to be installed which means an increase in expense. Furthermore, the fact that the feeding of the electric current must be effected to magnets which are constantly in motion means an additional expense.
The closest prior art known to the applicant in connection with this application is in the British Pat. No. 742,060 and the German Pat. No. 1,020,578.